Metabolism of Aromatic Amino Acid in Microorganisms |
| |
Authors: | Koichi Ogata Kazuko Uchiyama Hideaki Yamada Tatsurokuro Tochikura |
| |
Institution: | 1. Department of Agricultural Chemistry, Kyoto University, Kyoto;2. Research Institute for Food Science, Kyoto University, Kyoto |
| |
Abstract: | Phenylalanine ammonia-lyase, which catalyzes the conversion of l-phenylalanine to trans-cinnamic acid and ammonia, has been partially purified from the cells of Rhodotorula. Some of the properties of this phenylalanine ammoyia-lyase were investigated. The enzyme was stable in phosphate buffer of pH over the range of 6.0 to 7.0 On heating, the enzyme was stable up to 50°C, but above 60°C, it was destroyed. The enzyme activity was strongly inhibited by p-chloromercuribenzoate at 10?5 m and almost recovered by the addition of glutathione or mercaptoethanol at 10?3 m. The present enzyme preparation of Rhodotorula also catalyzed the deamination of l-tyrosine to trans-p-coumaric acid. trans-p-Coumaric acid was isolated from the reaction mixture and identified by its absorption spectra. The rates of deamination showed optima at pH 9.0 and 9.5 for l-phenylalanine and l-tyrosine, respectively. |
| |
Keywords: | |
|
|